A dental attachment is embedded in a denture base so as to attach to a keeper made of a soft magnetic material built in a tooth root by magnetic attractive force. The dental attachment comprises an attachment main body which has a magnetic body delivering magnetic attractive force and a cap which covers a head portion located on the opposite side of an attractive surface to attach the keeper of the attachment main body. The cap, made of a non-magnetic material, is installed in the attachment main body so as to be able to move between a contacting position (A) which contacts with the head portion and an extended position (B) which is far from the head portion for a certain distance.